Dental treatment units

ABSTRACT

A dental treatment unit comprises a housing, a dental hand appliance support arm connected to the housing for pivotal arcuate movement in a substantially horizontal plane relatively to the housing and a counterbalanced dental instrument tray support arm assembly which is connected to the hand appliance support arm for pivotal arcuate movement therewith.

United States Patent Behne et al. [451 Mar. 21, 1972 [54] DENTALTREATMENT UNITS [56] References Cited [72] Inventors: Ernst-AugustBehne; 0H0 Fleer, bOth 0f UNITED STATES PATENTS Erlangen, Germany l 1970M t al. [73] Assignee: Siemens Aktiengesellschaft, Erlangen, Ger- 3 5305 3 9/ aurer 8 32/22 many Primary ExaminerRobert Peshock [22] Filed:Oct. 20, 1969 Attorney-Richards and Geier App]. No.: 867,5] 1

Foreign Application Priority Data Oct. 26, 1968 Germany ..P 18 05 483.6

U.S. Cl ..32/22 Int. Cl ..A6lc 11/00 Field of Search ..32/22; 312/209[57] ABSTRACT A dental treatment unit comprises a housing, a dental handappliance support arm connected to the housing for pivotal arcuatemovement in a substantially horizontal plane relatively to the housingand a counterbalanced dental instrument tray support arm assembly whichis connected to the hand appliance support arm for pivotal arcuatemovement therewith.

7 Claims, 3 Drawing F igures PATENTEDHARZI I972 SHEET 1 BF 2 INVENTORS:E-A,Behne m. 0. FZeer TTO (LNG-BS PATENTEDMARZI m2 SHEET 2 [IF 2 INVENTORS; EP 3 5mm OFZEar GLJW gQM A To RN E55 DENTAL TREATMENT UNITSBACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to a dental treatment unit and is more particularly but notexclusively concerned with a dental treatment unit which is adapted tobe supported by a patients chair which is mounted on a base foradjustment in a generally vertical direction relatively to the base.

2. Description of the Prior Art In such dental treatment units it isknown to mount a horizontal support, which extends parallel to thelongitudinal axis of the chair, at one of its ends on the verticallyadjustable base part of the chair, and for a tubular upright to bemounted securely near its end which bears resiliently on the floorthrough the agency of an extensible part, on the free end of thehorizontal support. The free end of the horizontal support is situatedapproximately in the region of the forward seat edge of the chair, andthe dental unit is secured on the tubular upright to be rotatable aboutthe upright by means of clips. The head of the dental unit is adapted tobe inclined about a horizontal axis, and from one side surface of theinclinable head there can be pulled out a jib-like telescopic arm ofrelatively small cross section which at its free end carries a housingunit for dental hand appliances used for syringing and drilling and thelike. The extensible conduits to the hand appliances extend between theunit head and the hand appliance housing in the open and, as long as thehand appliances are in their housings, are slightly tensioned by awinding device for the flexible conduits which is arranged in the dentalunit. Owing to this construction, the dental unit with the telescopicarm can be pivoted about the tubular upright, the housing unit for thehand appliances describing, in a plane situated above the patient, anarc the radius of which is adapted to be varied by the variousselectable lengths to which the telescopic arm can be pulled out. Also,the height of the pivoting plane above the patient can be varied bydifferent inclinations of the dental unit head.

To complete the aforesaid dental unit there is also provided a tray onwhich instruments can be deposited and which is supported through theagency of linkage arms by a vertical telescopic tube which is alsosupported on the vertically adjustable chair part, by means of a secondhorizontal supporting arm which is secured by means of a vertical pivotbearing on the vertically adjustable chair part.

The invention proceeds from the realization that in a dental unit of thetype described it is disadvantageous that the hand appliance housingunit and the instrument table can only be adjusted separately from oneanother. At each adjusting operation, more particularly at thehorizontal pivoting of the hand appliance housing unit in the sense ofadapting it to a modified working position on the part of the dentist,re-adjustment of the instrument table is also necessary and in the caseof the known unit this has to be carried out additionally to theadjustment of the hand appliance housing unit.

The main object of the invention is to provide a dental treatment unitin which the aforesaid disadvantages are minimized or eliminated.

SUMMARY OF THE INVENTION According to the present invention there isprovided a dental treatment unit comprising (a) a housing, (b) a dentalhand appliance support arm which is connected to the housing for pivotalarcuate movement in a substantially horizontal plane, relatively to thehousing, and (c)'a counter balanced arm assembly connected to thesupport arm for pivotal arcuate movement therewith, said assemblyincorporating a hollow arm and a support arm which carries an instrumenttray and which is linked to the hollow arm to form therewith aparallelogram linkage disposed within said hollow arm and which permitslinear movement of the tray towards and away from the housing.

As a result, at each horizontal adjustment of the support arm, theinstrument tray moves also, and thus always remains in the vicinity ofthe hand appliances which are adjusted to the particular positiondesired by the dentist in each case. The convenient arrangement consistsin that both the support arm and also the counterbalanced arm assemblyare pivotably mounted on a support casing which is securely connected toa vertical pivot bearing. This measure facilitates assembly ordismantling work on the dental unit since as a result the support arm,the arm assembly and the support casing form a single unit.

An advantageous further development of the invention consists in makingthe hollow arm adapted to be coupled to the arm by means of press studmeans. In the coupledup state, the instrument tray also accompanies anyvertical movement of the hand appliance housing unit and at the sametime retains its horizontal position in space.

It is also convenient to provide the underside of the arm with a recessin which the hollow arm can be housed over its entire length. If thehollow arm is lying in this recess, the overall height of the supportarm remains unaltered. Increasing the height would in fact be a nuisancewhen the support arm is swung over the patient.

If a spittoon unit is supported on the dental unit according to theinvention, there is a risk that the arm assembly situated below thesupport arm will impinge on the spittoon unit when the support arm isswung over the latter. In order to eliminate this risk, it is proposedthat a part of the hollow arm which is supported in the support casingand is extended below the horizontal pivots is constructed as anabutment and on the dental unit there is provided a counter-abutmentwhich, on pivoting of the arm assembly about the vertical pivotmounting, projects into the path of the abutment and, when the armassembly approaches the spittoon unit, causes the arm to be lifted. Thecounter-abutment is advantageously constructed as a cam disc with a nosedirected towards the spittoon unit.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the invention may bemore fully understood an embodiment in accordance therewith will now bedescribed by way of example with reference to the accompanying drawings,in which:

FIG. 1 shows a dental treatment unit connected to a patients chair in aninoperative position,

FIG. 2 shows the dental treatment unit of FIG. 1 in an operativeposition, and

FIG. 3 shows constructional details of the counterbalanced arm assemblymounting.

DESCRIPTION OF THE PREFERRED EMBODIMENT In FIG. 1, 1 designates apatients chair, which consists of a head part 2, a back rest 3, aseatpart 4, a foot part 5, a base 6 supported on the floor, a verticallyadjustable base part 7 connected to the seat part 4, and a parallelogramarm 8 connecting the two parts 6 and 7 to one another. The dot-dash line9 represents the longitudinal axis of the patient's chair.

The dental unit includes an upright elongate housing 10 which isdisposed to one side of, i.e., the left-hand side of the patient's chair1 with its longitudinal extent parallel to the longitudinal axis 9 ofthe patient's chair I. On the upper surface 11 of the housing 10, asupport arm 12 is connected at one end for pivotal arcuate movement in asubstantially horizontal plane about a substantially vertical axis 15near the narrow end 13 adjoining the foot part 5 of the patients chair1, through the agency of a support casing 14. The arm 12 is alsoconnected to the casing 14 for pivotal upward and downward movementabout a horizontal axis in the form of a pin 16. Dental hand appliancesare carried by the other free end of the arm 12, housings 17 and 18 fora turbine-type handpiece l9 and a micromotor handpiece 20 being insetinto the end face 21 of the arm 12, and a dental syringe 22 rests in ahousing 23 fixed on the upper surface of the arm 12. Below the handappliances 19, 20, 22 a dental instrument tray 24 is supported in amanner to be described. A stirrup-shaped handle 25 is also mounted onthe free end of the arm 12 between the syringe 22 and the handpieces 19,20.

That part of the upper surface 11 of the housing which is nearer thehead part 2 of the patient's chair 1 is constructed as a spittoon unitand comprises at the upper surface 11 a removable spittoon bowl 26, amouth rinsing tumbler 27 and the mouth rinsing tumbler filling device28. At the narrow end 29 of the housing 10 there are also arrangedoperating pushbuttons 30 (for filling the tumbler, operating the syringeand the like) and below these operating pushbuttons 30 a strongactionsuction hand appliance 31 and a saliva extractor appliance 32 arearranged to be removable from respective supports in a housing 33.

As shown in FIG. 2, an elongate support member in the form of asubstantially horizontal guide rail 34 which extends parallel to thelongitudinal axis 9 of the patients chair 1 is mounted on the verticallyadjustable base part 7. A carriage 35 supporting the dental unit issupported to be displaceable lengthwise of the chair (arrow 37) by meansof bearings in the form of rollers 36 (for the sake of simplicity onlyone roller is illustrated) and to be lockable by means of releasablelocking means constituted by an electromagnetic brake 38. FIG. 2 alsoshows the way in which the tray 24 situated below the hand appliances19, 20, 22 is supported. The tray 24 is supported by a counterbalancedarm assembly 39 which is disposed below the arm 12 and which is mountedat one end for pivotal movement on two horizontal axes 40 and 41 whichare situated one above the other. The axes corresponding to these axes40 and 41 at the tray-side end of the parallelogram arm are designatedas 42 and 43. For substantially horizontal pivoting of the tray 24towards and away from the housing 10 there is arranged between thetray-side end of the arm assembly 39 and the tray itself a horizontalpivoting tray support arm 44. At the undersurface of the arm 12 there isa recess 45 in which the hollow arm 48 of the arm assembly 39 can behoused over its entire length. In this recess 45 the hollow arm 48 canbe connected-up to the arm by means of press stud means comprising astud part 46 which is fixed to the arm 48 and with which there isassociated a corresponding counterpart 47 within the recess 45.

FIG. 3 shows the mounting of the counterbalanced arm assembly 39 on thehousing 10. The arm assembly 39 consists of the hollow arm 48 and twobars 49 and 50 disposed within the arm 48. The bars 49 and 50 aremounted on a link 51 to be pivotable about the horizontal axis 41 andthe arm 48 is mounted on the link 51 to be pivotable about thehorizontal axis 40. The hollow arm 48 is linked to the tray support arm44 in the manner described to form therewith a parallelogram linkagewhich permits linear movement of the tray towards and away from thehousing 10. Counterbalancing is effected by a spring which is situatedin the arm 48 and which is not shown in order to leave the drawingeasier to read. The link 5] stands on a fitting 52 which itself isconnected fast by means of spacer pins 53 to the underside of the casing14. Secured on the arm 48 is a stirrup-shaped extension 54 which extendsthrough two openings 55, 56 in the fitting 52 and on whose lower end acam-follower in the form of a roller 57 is rotatably mounted. Associatedwith this roller 57 to act as a counterabutment is a horizontal cam disc58 which is connected fast to the housing 10 beneath the pivot bearingand which comprises a nose 59 pointing in the direction of the spittoonunit (FIGS. 1 and 2) arranged on the housing. The form of the cam disc58 is so chosen that when the arm 12 is not situated above the spittoonunit the arm assembly 39 with its tray 24 can be situated lower than thespittoon unit. Then when the arm 12 is swung above the spittoon unit,the roller 57 contacts the cam disc 58. The nose 59 causes rotation ofthe extension 54 connected to the hollow arm 48 about the horizontalaxis 40 in the sense of lifting the arm assembly 39 and the instrumenttray 24.

We claim: l. A dental treatment unit having an instrument tray andcomprising a housing, a support member carried by said housing andhaving a pivot bearing a dental hand applicance support arm connected atthe housing to said support member, said pivot bearing having a verticalaxis to permit arcuate movement of said arm relatively to said housing,and a counterbalanced parallelogram arm assembly having a free endcarrying the instrument tray and an opposite end mounted on said supportmember below said support arm, said parallelogram arm assembly beingpivotable along with said support arm and comprising a hollow arm.

2. A dental treatment unit according to claim 1 comprising a pivotbearing with horizontal axis connected to said support member, wherebysaid support arm is movable upwardly and downwardly relatively to saidhousing.

3. A dental treatment unit according to claim 2, wherein said supportcomprises a casing, said pivot bearing supporting said casing upon saidhousing and permitting an arcuate movement of said casing relatively tosaid housing, said appliance support arm and said parallelogram armbeing pivotally connected to said casing.

4. A dental unit as set forth in claim 1, wherein a releasable lockingdevice is provided for securing the arm assembly to the hand appliancesupport arm, the device being constituted by press stud means on thehollow arm and said support arm.

5. A dental unit as set forth in claim 3 and further including a dentalspittoon unit mounted on the housing, wherein a cam is rigidly securedto the housing beneath the bearing and the support casing, acam-follower element is secured to an extension of the hollow arm, whichextension projects through the bottom of the casing whereby, when thehand appliance support arm is pivoted arcuately over the spittoon unit,the cam element cooperates with the cam to lift the counterbalanced armassembly above the spittoon unit.

6. A dental unit as set forth in claim 5, wherein the cam is providedwith a nose which projects towards the spittoon unit.

7. A dental treatment unit housing an instrument tray and comprising ahousing, a support member carried by said housing and having a pivotbearing a dental hand appliance support arm connected at the housing tosaid support member, said pivot bearing having a vertical axis to permitarcuate movement of said arm relatively to said housing, a counterbalanced parallelogram arm assembly having a free end carrying theinstrument and an opposite end mounted on said support member below saidsupport arm, said parallelogram arm assembly being pivotable along withsaid support arm and comprising a hollow arm, said hand appliancesupport arm having the shape of a housing opening toward said armassembly and enclosing said hollow arm, and a releasable locking devicehaving press stud means on said hollow arm and said appliance supportarm and securing said arm assembly to said appliance support arm.

1. A dental treatment unit having an instrument tray and comprising ahousing, a support member carried by said housing and having a pivotbearing a dental hand applicance support arm connected at the housing tosaid support member, said pivot bearing having a vertical axis to permitarcuate movement of said arm relatively to said housing, and acounterbalanced parallelogram arm assembly having a free end carryingthe instrument tray and an opposite end mounted on said support memberbelow said support arm, said parallelogram arm assembly being pivotablealong with said support arm and comprising a hollow arm.
 2. A dentaltreatment unit according to claim 1 comprising a pivot bearing withhorizontal axis connected to said support member, whereby said supportarm is movable upwardly and downwardly relatively to said housing.
 3. Adental treatment unit according to claim 2, wherein said supportcomprises a casing, said pivot bearing supporting said casing upon saidhousing and permitting an arcuate movement of said casing relatively tosaid housing, said appliance support arm and said parallelogram armbeing pivotally connected to said casing.
 4. A dental unit as set forthin claim 1, wherein a releasable locking device is provided for securingthe arm assembly to the hand appliance support arm, the device beingconstituted by press stud means on the hollow arm and said support arm.5. A dental unit as set forth in claim 3 and further including a dentalspittoon unit mounted on the housing, wherein a cam is rigidly securedto the housing beneath the bearing and the support casing, acam-follower element is secured to an extension of the hollow arm, whichextension projects through the bottom of the casing whereby, when thehand appliance support arm is pivoted arcuately over the spittoon unit,the cam element cooperates with the cam to lift the counterbalanced armassembly above the spittoon unit.
 6. A dental unit as set forth in claim5, wherein the cam is provided with a nose which projects towards thespittoon unit.
 7. A dental treatment unit housing an instrument tray andcomprising a housing, a support member carried by said housing andhaving a pivot bearing a dental hand appliance support arm connected atthe housing to said support member, said pivot bearing having a verticalaxis to permit arcuate movement of said arm relatively to said housing,a counter balanced parallelogram arm assembly having a free end carryingthe instrument and an opposite end mounted on said support member belowsaid support arm, said parallelogram arm assembly being pivotable alongwith said support arm and comprising a hollow arm, said hand appliancesupport arm having the shape of a housing opening toward said armassembly and enclosing said hollow arm, and a releasable locking devicehaving press stud means on said hollow arm and said appliance supportarm and securing said arm assembly to said appliance support arm.